Such devices have become known as so-called mid or soft lasers. They are utilized for the treatment in various areas such as in rheumatology, dermatology, neurology or in dental medicine. The treatment with laser rays is painless and causes either a warming nor a macrochemical change of the tissue. The laser radiation acts in a stimulating manner on the cell activity and activates therewith the body's own healing powers; it acts above of all antiphlogistically, antiedematous and pain relieving and is also free of any side effects.
A mid-laser is known which contains an HeNe-laser and emits a radiation having a wavelength of 633 nm. This radiation is conducted via flexible glass fibers to the location where irradiation is to occur. With this, the original polarized laser radiation is depolarized. Such lasers are preferably utilized for treating wounds.
In addition, mid-lasers are known which in addition comprise a second laser which emits a radiation of a wavelength of 904 nm. Here the rays are conducted directly to the location of the irradiation, that is, without optical elements being interposed. Because of this, such a device is most difficult to manipulate.
With these known mid-lasers, the laser beam is directed across the irradiation field in the form of a scanning raster. This has the disadvantage that the power density over this field is distributed unevenly since the power density at and near the reversal point is higher than in the regions lying therebetween.
With the known mid-lasers having a laser emitting at 904 nm, this laser is pulsed with the pulse frequency being adjustable and reaching up to approximately 5 kHz in the upper range. The semiconductor diodes utilized deliver only a low power in the timed average value which generally is at approximately 5 mW and therebelow.